Study of pesticides in shallow groundwater and surface water to help decision makers evaluate and manage pesticide application practices to protect drinking water resources, especially deeper, potable groundwater as well as aquatic species.

Cooperative national project with the Federal Highway Administration (FHWA) to evaluate FHWA's guidelines for highway-runoff quality. Links to searchable online bibliography of related publications by the USGS, EPA, FHWA, and state agencies.

Report on the use of regression equations from measurements made by water quality monitors and analytical results of manually collected samples estimating nutrient, bacteria, and other constituent concentrations to study streams in Kansas.

Homepage for USGS national surface-water data with more than 850,000 station years of time-series data for stream levels, streamflow (discharge), reservoir and lake levels, surface-water quality, and rainfall plus real-time data and tutorial.

Homepage of the Office of Water Quality programs on the quality of the Nation's surface water and ground water resources, with links to general information, quality assurance, software, data, publications, USGS facilities, techniques, and programs.

Stream discharge and nitrate concentration increased downstream of the burned area during snowmelt, but these were probably within the treatment capacity of most drinking-water plants, and limited changes were observed in downstream ecosystems.

Homepage for description of the National Stream Quality Network (NASQAN), a long-term program monitoring the concentrations and flux of sediment and chemicals in the Nation's largest rivers (Mississippi, Columbia, Colorado, Rio Grande, and Yukon).

Reports concentration of organic compounds here, to serve as a baseline against which future measurements can be compared and to provide a general assessment of the quality of local water treatment efforts.

In all, 56 compounds were detected in samples collected approximately monthly during 2003-05 at the intake for the Clackamas River Water plant. On the basis of this screening-level assessment, adverse effects to human health are assumed to be negligible.

We identified six compounds at concentrations less than human-health benchmarks, but within a factor of 10 of those limits. Those compounds might warrant further study to understand their transport and fate within the watershed.

The 258 organic compounds in this assessment are man-made: pesticides, solvents, gasoline hydrocarbons, personal-care and domestic-use products, pavement and combustion-derived compounds. None were found in concentrations deemed dangerous at this time.

Measured concentrations of many compounds in water people use. Some compounds are regulated as health hazards; a few of these were over the benchmark limits. Others may become issues of concern, so studies such as this give us helpful background levels.

Describes and illustrates that a broad range of chemicals found in residential, industrial, and agricultural wastewaters commonly occur in mixtures at low concentrations downstream from areas of intense urbanization and animal production.

Upcoming interagency study to assess status of ecological conditions, their relationships with contaminants and nutrients, anthropogenic factors affecting these, and develop models that may predict these ecological conditions.

In 2005, about 29.2 million gallons per day (Mgal/d) of water were withdrawn here, including about 26.8 Mgal/d from groundwater sources and 2.45 Mgal/d from surface-water sources. Rice irrigation accounted for 74 percent (21.7 Mgal/d) of the total.

In 2005, about 30.6 million gallons per day (Mgal/d) of water was withdrawn here, including about 30.4 Mgal/d from groundwater and 0.1 Mgal/d from surface water. Industrial use, primarily for wood products, accounted for about 72 percent (22 Mgal/d).

In 2005, about 15.8 million gallons per day (Mgal/d) of water were withdrawn, including 4.12 Mgal/d from groundwater and about 11.7 Mgal/d from surface-water sources.Public supply use accounted for about 78 percent (12.4 Mgal/d) of the total water withdra

In 2005, about 72.9 million gallons per day (Mgal/d) of water were withdrawn here, including about 7.70 Mgal/d from groundwater sources and 65.2 Mgal/d from surface-water sources. Public-supply use accounted for about 71%, and power generation 19%.

Summarizes information on the water resources of Lafayette Parish, Louisiana. Information on groundwater and surface-water availability, quality, development, use, and trends is based on previously published reports.

In 2005, about 6.67 million gallons per day (Mgal/d) of water were withdrawn here, including about 6.46 Mgal/d from groundwater sources and 0.21 Mgal/d from surface-water sources. Public-supply use accounted for about 76 percent (5.06 Mgal/d) of the total

In 2005, about 9.52 million gallons per day (Mgal/d) of water were withdrawn, including about 9.33 Mgal/d from groundwater and 0.19 Mgal/d from surface-water. Public supply use accounted for 70% of the total.

The report describes a strategy for monitoring, modeling, and research activities to support management decisions to improve water-quality conditions in the Mississippi River Basin, reduce hypoxia in the northern Gulf of Mexico, and improve conditions for

Acidified soils caused toxic aluminum in 66 percent of 565 assessed streams. Diatoms and aquatic macroinvertebrates were moderately to severely affected. These effects have not improved in areas surveyed in the early 1980s

Chloride concentrations in this river have historically been high due to natural saltwater springs and seeps from geologic formations. We monitor the water to help assess the progress of human efforts designed to mitigate this problematic salinity.

Stream water quality is affected by amount of impermeable surface in the basin; construction; reservoirs; sanitary sewer systems; land use and population density; road salt; animal waste; lawn and agricultural fertilizers, pesticides, and herbicides.

Water from this reservoir will be used more extensively by the city, so we are developing methods of assessing the water quality in real time by measuring characteristics of stream flow that correlate with important water quality data.

The area contributing recharge to this aquifer is undergoing rapid growth, generating more wastewater. We found that nitrate, a major component of wastewater and a nutrient that can degrade water quality, has increased in the creeks in this area.

Sampling for pesticide contamination in four major rivers in in the Bighorn and North Platte River Basins, begun in 2006 and resampled in 2009 and 2010 revealed concentration at levels below the standards for drinking water.

Sulfate deposition to high-elevation areas has decreased here as a result of reductions in SO2 emissions. Nitrate deposition did not change, whereas ammonium deposition increased, particularly at sites near urban and agricultural areas.

Detailed information on Total Maximum Daily Load, the total quantity of a pollutant that a stream can carry and still conform to water quality standards, used as a measurement in the monitoring, assessment, and remediation of polluted waters.

Water quality is important here because this reservoir is the primary supply for Wichita, Kansas. Due to low streamflow during the monitoring period, we expect suspended sediment and phosphorus to be more variable in the future.

Outlines tactical problems that make it difficult for beach managers to use scientific information to make beach closure and advisory decisions. Explains methodologies we are using to address those problems and better prepare local decision makers.

The Sacramento-San Joaquin River Delta is the hub of California's water system and an important habitat for fish and wildlife. USGS research has provided resource managers and other stakeholders with a good understanding of how pesticides enter the Delta.